Neuro Flashcards
(106 cards)
1
Q
Neuro cells
A
Neuron: excitable
Astrocyte: structural, most abundant
Oligodendrocyte/Schwann cell: myelin
Microglia: macrophage
Ependyma: CSF producing/regulating
2
Q
Phases of action potential
A
RMP
Depolarisation
Upstroke: Na influx, delayed K efflux
Repolarisation: VGSC close
Hyperpolarisation
3
Q
Factors affecting action potential propagation
A
Axon diameter
Myelinated neuron
4
Q
Parkinson’s drug
A
Pramipexole: dopamine receptor agonist
5
Q
Vesicular protein that mediates exocytosis of neurotransmitter
A
SNARE proteins
6
Q
Types of receptors for neurotransmitters
A
Ionotropic(fast): Glu, GABA for CNS, ACh for NMJ
GPCR(slow): ACh, DA, NA, 5HT
7
Q
Types of Glu receptors
A
AMPA: fast
NMDA: slow
8
Q
Effect of Glu
A
Excitatory
Na influx
Depolarisation
9
Q
Effect of GABA
A
Inhibitory
Cl influx
Hyperpolarisation
10
Q
Compare PNS and SNS visceral motor neurons
A
Parasympathetic: long pre(ACh), short post(ACh)
Sympathetic: short pre(ACh), long post(NA)
11
Q
CSF compared to blood plasma
A
Lower pH
Less glucose
Less protein
Less K
12
Q
Motor tract for voluntary movement(pyramidal)
A
Corticospinal tract: anterior(trunk), lateral(limb)
Corticobulbar tract: face muscles
13
Q
Motor tract for involuntary movement
A
Vestibulospinal
Tectospinal
Reticulospinal
Rubrospinal
14
Q
Sensory tracts
A
Dorsal column pathway: fine touch, vibration, proprioception
Spinothalamic tract: pain, temperature, crude touch
15
Q
Dorsal column pathway tracts
A
Gracile tract: lower limb
Cuneate tract: upper limb
First order synapse in medulla, second order decussates in medulla and synapses in thalamus, third order to somatosensory cortex
16
Q
Spinothalamic tract divisions
A
Pain and temperature(lateral) Crude touch(anterior)
First order synapses in grey matter of spinal cord, second order decussates at same level and synapses in thalamus
17
Q
Layers of fasciculi of PNS nerves
A
Epineurium
Perineurium
Endoneurium
18
Q
Proprioceptors
A
Muscle spindles: muscle length change
Golgi tendon: tendon tension change
Joint receptors: start/end of movement
19
Q
Sympathetic outflow/trunk
A
T1-L2: white ramus communicans
C1-C8: ascending sympathetics
L3-Co: descending sympathetics
20
Q
Sciatica causes
A
Disc herniation(slipped disc): bulge
Spinal stenosis: narrowing
Spondylolisthesis: slippage
Non-disc: malignancy, arthritis, bone growth
21
Q
Cranial nerves that emerge at midbrain
A
CN 3 and 4
22
Q
Cranial nerves that emerge at pons
A
CN 5-8
23
Q
Cranial nerves that emerge at medulla
A
CN 9, 10, 12
24
Q
Frontal lobe function
A
Motor function
Cognitive function
25
Parietal lobe function
Sensation
Sensory language
Spacial orientation & self-perception
26
Occipital lobe function
Process visual info
27
Temporal lobe function
Process auditory info
| Emotion
28
Limbic lobe
Hippocampus
Cingulate gyrus
Amygdala
Learning, memory, emotion, motivation and reward
29
Insular cortex
Deep to lateral fissure
| Visceral sensation, autonomic control
30
White matter tracts in cerebral cortex
Association fibres: within the same hemisphere
Commisural fibres: homologous structures between hemispheres(corpus callosum and anterior commisure)
Projection fibres: lower brain structures via internal capsule (corona radiata)
31
Frontal lobe supplementary vs premotor area
Supplementary: internally cued
Premotor: externally cued
32
Cortical(lobe) functions after lesion
```
Frontal: personality change
Parietal: contralateral neglect
Temporal: agnosia, anterograde amnesia
Broca’s: speech production
Wernicke’s: speech comprehension
Visual assiciation: visual interpretation deficit
```
33
Types of haemorrhages
Extradural: arterial, high pressure
Subdural: venous, low pressure
Subarachnoid: circle of Willis, aneurysm
Intracerebral: chronic hypertension
34
Causes of stroke
Thromboembolic(85%)
| Haemorrhage(15%)
35
Symptoms of stroke
One sided face drooping
Cannot lift/maintain both arms
Slurred speech
36
Stroke risk factors
```
Age
Hypertension
Cardiac disease
Smoking
Diabetes mellitus
```
37
Anterior cerebral artery embolism symptoms
```
Contralateral paralysis(likely legs)
Affected intellect, cognition
```
38
Middle cerebral artery embolism symptoms(classic stroke)
```
Contralateral paralysis(likely arms)
Aphasia(left sided lesion)
```
39
Posterior cerebral artery embolism symptoms
Visual deficits: homonymous hemianopia, face blindness
40
Motor cortex lesion
Apraxia: skilled movement disorder caused by stroke/dementia at premotor cortex/supplementary motor area
Motor neuron disease: amyotrophic lateral sclerosis(ALS)
41
Upper motor neuron lesion signs
```
Spasticity
Hypertonia
Hyperreflexia
Babinski’s sign
Dysphagia
```
42
Lower motor neuron lesion signs
Muscle atrophy & wasting
Hypotonia
Hyporeflexia
Fasciculations
43
Basal ganglia disorders
Parkinson’s(substantia nigra): degeneration of dopaminergic neurons
Huntington’s(striatum): degeneration of GABAergic neurons
Ballism(subthalamic nucleus): usually stroke causing uncontrolled flinging of extremities
44
Parts of cerebellum and effect of damage to that area
Spinocerebellum: abnormal gait/stance
Vestibulocerebellum: gait ataxia and fall tendency
Cerebrocerebellum: speech
45
Outer ear function
Protection
Capture sound
Amplify some frequencies
46
Middle ear function
Amplify by focussing vibrations from large surface area(tympanic membrane) to small surface area(oval window)
47
Middle ear bones
Malleus
Incus
Stapes
48
Inner ear function
Transduce vibration into nervous impulse
49
Layers of the cochlea
```
Scala vestibuli(bony, perilymph)
Scala media(membranous, endolymph and contains organ of Corti)
Scala tympani(bony, perilymph)
```
50
Difference between perilymph and endolymph
Perilymph high Na
| Endolymph high K
51
Basilar membrane arrangement
Tonotopically
Base: narrow and tight(high freq)
Apex: wide and loose(low freq)
52
Organ of Corti cells and relation to tectorial membrane
1 column of inner hair cells
3 columns of outer hair cells
OHCs in constant contact with tectorial membrane
Deflection of tectorial membrane ->depolarisation
53
Organ of Corti afferent/efferent nerves
IHC: 95% of afferent info
OHC: 95% of efferent info
54
Name of hairs in auditory system and function
Sterocilia
| Deflection towards longest cilium opens K channels->depolarisation
55
Classification of hearing loss
Conductive(outer/middle ear)
Sensorineural(inner ear/nerve)
Mixed(conduction/transduction)
56
Causes of hearing loss
Conductive: wax, foreign body, otitis, otosclerosis
Sensorineural: presbycusis, ototoxicity, CN VIII tumour
57
Hearing loss treatment
Treat underlying cause
Hearing aids: amplifies sound
Cochlear implant: replaces hair cells
Brainstem implant
58
Vestibular system inputs and outputs
Inputs: visual, proprioceptive, vestibular
Outputs: ocular reflex, postural control, nausea
59
Otolith organs and which one joins to SCC
Utricle, saccule
Semicircular canals have an ampulla that joins to utricle
60
What kind of cilia do vestibular hair cells have
Have kinocilium and stereocilia
| Endolymph movement->depolarisation
61
Vestibular system functions
Detect head movement
Keep images fixed during movement
Postural control
62
Vestibular hair cells potential
Excitatory: hair moves toward kinocilium
Inhibitory: hair moves away
63
Which part of vestibular system detects accelerations
Linear: utricle(horizontal), saccule(vertical)
Angular: cupula moves and displaces hair cells in SCC, which work in pairs
64
Vestibular reflexes
Vestibulo-ocular: vestibular and oculomotor nuclei->images stay fixed
Vestibulospinal: prevent falling and postural control
65
Symptoms of balance disorder
Dizziness
| Vertigo
66
Balance disorder locations
Peripheral(labyrinth +/- CN VIII): vestibular neuritis, BPPV, Meniere’s disease
Central: stroke, multiple sclerosis, tumour
67
What is BPPV
Benign paroxysmal positional vertigo
Crystals dislodged and enter SCC
68
What is Meniere’s disease
Increased fluid buildup in labyrinth
69
Layers of tear film
Superficial lipid layer: reduce evaporation
Aqueous tear film
Mucinous layer
70
Layers of the eye
Sclera: tough, opaque, high water content
Choroid: blood vessels, iris that controls light levels
Retina: blind spot no photoreceptors, macula contains fovea that has high cones and low rods
71
Layers of retina
Outer: photoreceptors
Middle: bipolar cells(process local signal)
Inner: retinal ganglion cells
72
Types of photoreceptors and function
Cones: colour, central vision, fast response
Rods: night, peripheral vision, slow response, more sensitive to light than cones
73
Causes of ametropia
Myopia:
Rays converge anterior to retina
Excessive long globe
Excessive refractive power
Hyperopia:
Rays converge posterior to retina
Excessive short globe
Insufficient refractive power
Astigmatism:
Rays converge at 2 focal lines
Refractive media not spherical
Presbyopia:
Loss of accommodation
>40 years
Distant vision intact
74
Effect of lesion at optic chiasm
Bitemporal hemianopia
75
Effect of lesion posterior to optic chiasm
Homonymous hemianopia:
Right lesion->left HH
Left lesion->right HH
76
CN III palsy symptoms
Down and out
| Droopy eyelid
77
CN VI palsy
Affected eye cannot abduct
| Double vision
78
Optokinetic nystagmus reflex
Oscillatory eye movement
79
Types of cerebral inflammation
Meningitis
Encephalitis
Cerebral vasculitis
80
Red flags for headache
```
Onset
Meningism(photophobia, stiff neck, fever)
Systemic symptoms
Neurological symptoms(Horner’s)
Orthostatic
Strictly unilateral
```
81
What is carotid/vertebral artery dissection and management
Splitting of arterial wall
Carotid more common
Carotid: phantom of opera headache
Vertebral: occipital headache
Aspirin/anticoagulant
MRI
82
Causes of unilateral headache
Temporal arteritis
Migraine
Cluster headache
83
Meningitis symptoms
```
Fever
Stiff neck
Photophobia
Headache
Confusion
```
84
Meningitis management
Treat then diagnose
Antibiotics
Lumbar puncture
CT/MRI
85
Low pressure headache symptoms and management
Orthostatic headache
Rehydration
Caffeine
Blood patch
86
What is chiari malformation
Normal brain that sits low in the skull
| Causes cough headache
87
What is trigeminal neuralgia and management
Neurovascular conflict at point of entry of nerve into pons
Electric shock like pain triggered by harmless stimuli
Anticonvulsants
Posterior fossa decompression
88
What is cervical spondylosis
Narrowing of joint space due to joint disc
| Bilateral occipital pain worsened by neck movement
89
Migraine symptoms
Visual vertigo
| Unilateral pain
90
Migraine phases
```
Prodrome
Aura
Headache
Resolution
Recovery
```
91
Migraine treatment
Avoid triggers(diet, sleep, weather)
Aspirin, ibuprofen(NSAIDs)
Paracetamol(anti-emetics)
92
Migraine prophylaxis
```
Antidepressants
Beta blockers
Calcium channel blockers
Anticonvulsants
Erenumab(disables calcitonin gene related peptide)
```
93
What is tension headache and management
Tight muscles around head/neck bilaterally
NSAIDs, paracetamol, antidepressants
94
What is cluster headache and what is it accompanied by
Severe unilateral pain
Conjunctival redness
Nasal congestion
Eyelid oedema
95
Cluster headache management
Inhaled oxygen
| Subcutaneous/nasal sumatriptan
96
Types of hearing tests
```
Pure tone audiometry(hearing acuity)
Audiometry(audiogram)
Tympanomentry(middle ear condition&eardrum mobility)
Otoacoustic emissions(newborn screening)
Auditory evoked potentials
Auditory brainstem response(babies)
```
97
Colour blindness
Deuteranomaly: red
Achromatopsia: full
98
Parkinson’s symptoms
```
Bradykinesia
Akinesia
Rigidity
Tremor at rest
Hypomimic face
```
99
Cerebellar dysfunction signs
```
Scanning speech
Intention tremor
Ataxia
Dysmetria
Dysdiadochokinesia
```
100
Alzheimer’s features
Amnesia
Amyloid plaques, tau
Hippocampus
101
Vascular dementia features
Step wise deterioration
| Stroke related
102
Lewy body dementia features
Cognitive impairment
Parkinsonian symptoms
Visual hallucinations
Fluctuating cognition
103
Frontotemporal dementia features
Behaviour change
| Non fluent aphasia
104
Dementia investigations
MMSE(mini mental state exam)
MRI
Bloods
PET
105
Dementia management
Acetylcholinesterase inhibitors
Treat behavioural/psychological symptoms
Social services/occupational therapy
106
Dementia differential
Delirium
| Depression
